This invention relates to improvements in bridging for floor joists and, in particular, to a bridge member that accommodates variations in the spacing between joists and permits the installation of heat and air conditioning runs between the joists without sacrificing structural strength.
Wooden floor joists are commonly used in the construction of houses and similar structures as well as smaller commercial buildings. In order to increase the structural rigidity of the joists and prevent squeaky floors and other problems caused by unwanted vibration and shifting, it is common practice to install bridging between the joists to minimize vertical and lateral deflection. As the joists are typically arranged in parallelism on selected center-to-center spacing, such as 16 inches (40 centimeters), the bridging extends transversely between adjacent pairs of joists and spans the approximately 16-inch space between each pair of joists and is installed in rows spaced longitudinally of the joists. The bridging pattern thus established materially increases the structural rigidity of the floor system.
Bridging in common use may comprise wooden or steel cross braces that are nailed in place, each bracing member extending from the top of one joist to the bottom of an adjacent joist to form a cross configuration when two bridging members are installed. This blocks or severely restricts the longitudinal passageway between the joists and typically results in the omission of the bridging between those pairs of joists between which heating and air conditioning runs are to be installed. Typically, the installers of mechanical runs simply remove the bridging previously installed during the rough-in construction in order to expedite the implacing of conduits or duct work. This results in spaces in the floor system throughout the structure that are devoid of bridging and presents regions of structural weakness that are subject to unwanted deflection.